The present invention relates to a pipe seal connection between confronting ends of two pipes which are mounted coaxially of each other and which are rotatable relative to each other and axially immovable relative to each other. More particularly, the present invention is directed to such a pipe seal connection which provides a seal to protect against a molten material passing through, particularly molten metals. Furthermore, the present invention is directed to an assembly including two such coaxially and relatively rotatably mounted pipes, such assembly being improved to include the pipe seal connection of the present invention.
Pipe seal connections of this type are required, for example, for certain applications in pipeline systems for molten metals, particularly molten aluminum. For example, in a sliding closure unit of the rotary type (such as disclosed in EP No. 0,040,692) having a discharge pipe executing a rotary movement when the sliding closure unit is actuated, the molten material must be guided by such rotary pipe into a stationary pipe. A pipe seal connection between two such pipes must permit relative rotation therebetween while ensuring a seal therebetween. Further, such connection must be constructed in a manner such that temporary freezing of the molten material or any incrustations do not adversely affect operation of the connection. In this regard, it must be kept in mind that molten materials, and particularly molten metals, generally are transported and used at temperatures only slightly above the respective melting points, for which reasons such materials tend to freeze or solidify.